The present invention relates to exhaust gas recirculation valves for use with internal combustion engines.
Exhaust gas recirculation (EGR) valves capture engine exhaust and selectively recycle the captured exhaust gas into the combustion chamber of the engine. Adding the exhaust gas to the air in the combustion chamber increases fuel economy and reduces undesirable emissions.
Conventional EGR valves include a magnetic actuator and a metering body. The actuator includes an elongate shaft. The metering body includes a metering chamber having a metering port. The metering chamber has an end that is associated with the intake manifold or intake vacuum of the engine. The metering port is connected to a source of exhaust gas and provides a passageway for the flow of exhaust gas into the metering chamber. The shaft extends contiguously in an axial direction from the actuator, through an orifice in the metering body, into the metering chamber, and through the metering port. An enlarged end of the shaft is disposed proximate the metering port. In a default position, the enlarged end of the shaft sealingly engages the metering port and prevents exhaust gas from entering the metering chamber. The metering port is opened when the shaft is disengaged or reciprocated from sealing engagement therewith, thereby allowing exhaust gas to enter into the metering chamber. Thus, the metering port and the reciprocal motion of the shaft selectively provide a passageway for exhaust gas to enter into the metering chamber and into the intake air stream of the engine.
EGR valves are designed for use with a particular engine. The EGR valve is bolted or otherwise attached to the engine, typically at the metering body. Different engines will typically have different mounting configurations to accommodate EGR valves. The EGR valve must be specifically designed with a metering body that mates with the mounting configuration of that particular engine model. Thus, an EGR valve designed for a particular model of engine will not likely be interchangeable with an EGR valve designed for use with a different model of engine. Furthermore, even if mounting configurations are standardized, different engine models typically require different relative configurations of the metering chamber and the metering port. Thus, each different type or model of engine typically requires an EGR valve that is designed specifically for use with that engine. Therefore, a supplier of EGR valves must have the capability to manufacture numerous and distinct designs of EGR valves for use with the different engine models.
Manufacturing numerous and distinct designs of EGR valves requires a manufacturer to maintain multiple manufacturing lines, multiple manufacturing processes, and design-specific tooling, thereby increasing the cost and resources required to manufacture each EGR valve. Component parts for each EGR valve design must be ordered, stored, and inventoried, thereby further increasing the cost and resources required to manufacture multiple designs of EGR valves. Furthermore, maintaining an inventory of EGR valves for use with each different type of engine results in substantially increased overhead costs for, and consumes the valuable floor space of, automobile manufacturers, parts suppliers, and repair shops.
Therefore, what is needed in the art is a modular EGR valve which can be used with a number of different models of engines.
Furthermore, what is needed in the art is an EGR valve design which reduces the number of component parts, number of manufacturing processes, and different tooling required to manufacture the valve.
The present invention provides a modular EGR valve for use with a plurality of internal combustion engines.
The present invention comprises, in one form thereof, an actuator subassembly and a metering subassembly. The metering subassembly defines a metering port and a metering chamber. The metering port and the metering chamber have a predetermined relative configuration. The metering subassembly is configured for being coupled to the actuator subassembly and for being coupled to an engine.
An advantage of the present invention is that the different metering subassemblies can be used with corresponding and different models of engines.
Another advantage of the present invention is that a common actuator subassembly is coupled to each of the different metering subassemblies, and thus only one actuator subassembly is required.
Yet another advantage is that the modular construction of the EGR valve reduces scrap and expedites repair procedures.